Low Cost Portable Fluidized Bed Dryer for Drying of different Crops

The drying characteristics for different crops (grains and vegetables) are analyzed using a fluidized bed dryer with respect to the moisture content, diffusivity and physical properties of grains and vegetables. Temperature dependence of mass transfer coefficients is established in terms of Arrhenius type of relation. Drying constant and shrinkage constant of different shaped samples are also studied. Simple mathematical expressions are developed relating volumetric shrinkage constant with drying constant. Dimensionless groups viz. Reynolds number, Schmidt number, and Sherwood number are determined at different drying conditions, mass transfer coefficients are determined. The physical properties of samples are also analyzed at different levels of moisture contents. The performance of fluidized bed dryer is investigated by using different samples. The effects of different system parameters on the drying performances are also studied. Artificial Neural Network and Taguchi analysis are used to validate the developed correlations for drying characteristics. Again a portable tapered fluidized bed dryer is designed to provide drying in turn storing opportunity to farmers.